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nnrrnn srarns Parnu s l ADAM S. CAMERON, OF NEV"YORK, N. Y.

CUT-OFF VALVE FOR STEAM-ENGINES.

Speccaton of Letters Patent No.

To all whomfitmay `concern:

Be it knownl that I, ADAM lSoo'i'r CAM- ERoN,.of the city, icounty, and State of New York,; have linventedvcertain new and useful Improvements in .Cut-Off VValves of Steam-Engines; and I do hereby declare that the following is a full,clear, andiexact description thereof, reference being had to theaccompanying drawings, making part of this specification, in which-i` 1 1 Figure-1, is longitudinal` vertical section of the steamchest of a steam engine with my .improved cut-0E` valvesgendFig. 2 a horizontal section thereof taken at the line Aci,ofFig;1. t 1" The sameA letters indicate like parts in all the tiguresnr 'f 1 l i The: obj ect' of the i first i part oflmy vsaid invention is to relieve slide cut-0H `valves from the pressure of the steam at thetime of opening the steam` ports.` andy thereby save much ofvzfthe power heretofore :expended in opening suchxvalves;A andV this `part of my said invention consists in combining with the', slide valve Awhich opensfthe steam ports, trip valves :which are hinged to t-he slidel valve to open and close the steam passages in the said slide valve and so operated by the sliding ofthe steam valve as`to open the steam passagesand fclose `themsuddenly at any required period, to cut otta the steam, the seat of' thesteam slideyvalve being' so formed that at the periodsof lifting ythe hingedvalves the l steam passages in the Asaid slide valve shall be beyond the valve seat that the steam in thesteam chest may at the time have access tothe under face ,of the hinged valves toslrelieve them ofthe pressure of steam `:which` would otherwise have to be overcome inopeningthem. And the'object of the secondpart of said invention is also to regulate the period o-f cutting ott the steam in such valves at anydesired part of the stroke of the piston; and consists incombining with the said trip hinged valves and the slide valve a cone or equivalent device, made adjustable by a governor or other means to vary the periods when the mechanism which liberates the trip valves shall come in contact with it to eii'ect the tripping of the valves and cutting off the steam. And the object of the last part of my said invention is to adjust the period of closing the two trip hinged valves relatively to each other, and to the strokes of the piston; and this part of my invention consists in mounting 22,935, dated February 15, 1859.

the cone, or equivalent, on which the mechanism'o'f the hinged valves acts to effect the disengagement onan eccentric arbor passing through to the'outside'of the steam chest so"`that by turning the said arbor the eccentri'city ofthe said conewill admit of adjustingfits periphery to thel tripping' mechanismofthe two `valves as'may be desiredand while the engine Lis in motion. A

In the accompanying 1 drawings (a) repre sents the steam chest of a steam engine, with the usual slidevalve` (b)`to be operated" in the usual manner, and adapted to slide on the valve seat (c) -formedas usual with twoV Y steam ports (d, d) and with eXhaustports (e).` The upper part of the slide valve is provided `withftwo setsof ears (f, to receive thefhinge or fulcrum pins (g, Vg) of two hingedV valves (afk) the faces of which are adaptedjtoclose4 the two steam passages (2', i) =of the `slide valve; By the turning of the valves (71, 7i) on their hinge or fulcrum pins the said steam passagescan be opened or closed, and that these operations may be performed, each valve has an arm (j) 'to the upper .endofwhich is hinged a rod (7c) having a hook (Z) which when thevalve is openedI hooks `onto a standard The rod extends `some distance beyond the hook, s'o that when, bythe movements of the slide valve, the extreme end strikes against the face of' a cone or equivalent wedge stop or cam (to be presently described) the rod shall be unhooked that the valve may suddenly close to out oit1 thesteamf` And when thenslide valve approaches the end of its opposite movement the armV of the valve strikes against-a fixed stop (n) (which may be made adjustable) by which the hinged valve is opened and the rod hooked on to keep it op'enuntilfthe required period of cut' off. Both valves (k, t)"are in like manner provided with an arm, a hook rod and appendages; andtoinsureV the rapid closing of these valves when unhooked, if their weight be not suiiicient for this purpose, a spring may be employed and which may be applied in the manner represented at (o). This is a dat spring attached to the upper surface of the slide valve with the ends eX- tending over and bent to act on top of the two hinged valves as represented.

To the top of the steam chest is fitted a tube (p) with a ground or other suitable steam t-ight joint; and the end of this, outside the steam chest, is provided with ahand wheel (y) by which it can be turned. This tube is eccentric and to its bore is fitted a cylindrical rod (r) adapted to slide therein steam tight. The outer end of this rod may be connected with a governor or any other adjustable apparatus; and its lower end inside the steam chest carries a cone (s) placed between the inner ends of the two hook rods, so that by moving it in or out l the engineer can readily and with the utmost accuracy, adjust the periods of the relative closing of the two valves.

The seat (c) of the slide valve (b) projects but a short distance outside of the two steam ports, as represented at (t, t) that is to say, that part of the seat should be only a little greater in length than the length of the steam passages (i) so that in the movements of the valve the moment one of the steam passages passes off from its corresponding port (CZ) it shall pass beyond the valve seat that the steam in the chest may get under the hinge valve to balance the pressure before the hook rod strikes against its stop to lift the hinge valve and hook on the rod.

The parts being thus constructed it will be seen that when the slide valve is moved by the usual connection of the engine, in the direction of the arrow, and one of the steam passages opens its port, the steam passing through the steam passage and steam port (cl) will impel the piston of the engine, and when the piston has made the required portion of its stroke, the hook rod (7c) strikes against the cone (s) by which it is unhooked. This liberates the hinged valve (it) which instantly closes stopping the steam passage and hence cutting off the steam that it may act eXpansively. And on the return movement the steam passage (i) iirst passes olf from the steam port (d) and then begins to pass beyond the valve seat at (t) admitting the steam to the under face of the hinged valve which is thus balanced,

and then the opposite end of the hook rod (7c) strikes against the stop (n), lifting the valve and hooking on the rod to keep the valve open until the period for cutting olf the steam returns; the period being determined by the position of the cone, whether regulated by the governor, by the hand of the engineer, or by any other suitable means. The same movements take place alternately with the t-wo valves.

It will be obvious that a wedge or cam may be substituted for the cone, as the means for effecting the unhooking of the rods t0 trip or liberate the cut off valves; and so with the other parts, other devices may be substituted to perform the same offices or functions, so long as the principle or mode of operation which distinguishes my invention from all other things before known, remains the same.

IVhat I claim as my invention, and desire to. secure by Letters Patent, is-

l. The employment of the trip hinged valves with their hook rods and appendages for operating them, or the equivalents thereof, substantially as described, in combination with the slide valve, substantially as described, for cutting off the steam in steam engines as described.

2. I also claim in combination with the slide and the trip hinged valve operated substantially as described, the so forming the seat of the slide valve, relatively to the steam passages in the slide valve, substantially as described, as to admit the steam to the under face of the hinged valve and balance the pressure before they are opened, as set forth. Y

8. I also claim in combination with the slide and trip hinge valves combined and operating, substantially as herein described, the employment of the adjustable cone or its equivalent, substantially as described, t0 regulate t-he period of cutting off the steam as described. p

4. And I also claim the cone, or its equivalent, in combination with the eccentric tube, or its equivalent, substantially as described, as a means of adjusting the relative periods of closing the two valves, as set forth.

ADAM S. CAMERON. lVitnesses IVM. H. BISHOP, ANDREW DE LACY. 

